Injection device



Ap 1951 (5. w. FERGUSON INJECTION DEVICE Filed April 15, 1948 5 z M w mm a w n a m a m M a 1 file, V Ce, v v 10 i E r A Z 7 I J W 3 i 6 r w 5 3:; l 9 5 5 M 9 Z fiarmwd if HTTOR N E YS' Patented Apr. 24, 1951 UNITED STATES PATENT OFFICE INJECTION DEVICE Garwood W. Ferguson, Paterson, N. J., assignor to Becton, Dickinson-and Company, Rutherford, N. J., a corporation of New Jersey Application April 13, 1948, Serial No. 20,685 8 Claims. (01. 128-173) This invention relates to a structurally and functionally improved injection device and especially an apparatus to be employed in the in- Jection of medicament into tissue.

It is an object of th invention to provide an apparatus which may readily be operated by the physician or patient and in which, aside from associating medicament with the device, substantially no other eifort or time-consuming operations will be necessary. In other words, in order to potentialize the apparatus for operation, it will not be necessary to wind or otherwise tension a spring, to associate a flask of compressed fluid, such as CO2 with the apparatus, or otherwise to place the unit in a condition where it may perform an operative stroke. Rather, an apparatus is furnished which, at all times, will be ready for substantially instantaneous operation without any preparatory technique being resorted to.

A further object is that of providing an injection device, the working stroke of which will be substantially uniform throughout its entire range with no dimunition in power. Therefore the medicament may be discharged under substantially uniform and constant conditions. Moreover, the present apparatus will function in a desirable and satisfactory manner (within its functional limits) regardless of the amount of liquid which is to be discharged.

Another object is that of providing an apparatus of this nature which will embody rela tively few parts, each individually simple and rugged in construction, such parts being capable of ready assemblage, and when assembled, operating over long periods of time with freedom from difiiculties. Additionally the device will be compact and readily portable.

With these and other objects in mind, reference is had to the attached sheet of drawings illustrating practical embodiments of the inven tion and in which:

Fig. 1 is a longitudinal sectional view of one form of injection device, and

Fig. 2 is a somewhat enlarged and fragmentary View also in section, of a second form of the apparatus.

The present invention has primary reference to that type of injection device which is employed to inject medicament into the tissues without the aid of a skin-penetrating needle. In other words, the liquid to be injected is discharged in a, stream of relatively minute crosssectional area and this discharge is effected with such velocity that the skin is penetrated and the medicament is lodged in the underlying tissues in a desired pattern. With this in mind, the medicament-receiving chamber has been shown in the form of a cartridge or ampule extending beyond the main body of the device. It will be understood that numerous other structures for containing and delivering the medicament, might be employed. Therefore, except where otherwise indicated in the appended claims, the specific showings and following description are to be taken in an illustrative, rather than in a limiting sense, with regards to the medicament-enclosing structure.

With the foregoing in mind, the numeral 5 indicates the body of an ampule or cartridge which body is hollow and contains medicament. The outer end of this body may be formed with one or more discharge orifices 6 of minute crosssectional area. The upper end of the body conveniently terminates in a retaining flange I and a stopper 3 seals the interior of the body. This stopper may be formed of rubber or similar material and is conveniently impregnated with a lubricant or is otherwise treated so that it will not bind against the surfaces of the bore of body 5.

To secure the ampule or cartridge 5 against movement with respect to the body of the device, a loading cap in the form of a retaining ring 9 may have screw-threaded connection with the forward end portion is of the assembly. As shown, this ring will engage flange l of body 5 to prevent relative movement between the parts. The forward portion is of the assembly is secured by, for example, screw threads with the cylindrical body ll thereof. The rear end of the latter may be closed by a cap 92. The parts iii, El, and 12 are formed of non-magnetic material, conveniently brass.

Within the case II a solenoid assembly is dis posed. This conveniently includes a cylindrical body l3 to which end caps M and i5 are secured. The cap [4 may havean extension it having screw-threaded connection with the forward body portion I0, to prevent relative movements of the parts. The body i3 and caps it and i5 are preferably formed of iron. Enclosed within the same are the windings of a solenoid ll. In turn enclosed within these windings is a tube I 8 providing a solenoidcore. This tube is conveniently formed of brass. v spacers [9 may be disposed adjacent each end of the windings I 1 and interposed'between the same and the caps i4 and I 5.

The forward portion [0 of the assembly is.

Fiber washers or the holder rings 9 or 3|.

that other forms of medicament-containing formed with a bore 20, which aligns with the stopper 8 when a cartridge or ampule is mounted by the device. Reciprocable within the bore 20 is a plunger 2|. This plunger is also guided for movement by passing through the bore of a stop element 22. The latter is preferably formed of soft iron. The plunger should embody nonmagnetic characteristics and is therefore preferably formed of brass.

Attached to plunger 2| in any suitable fashion is an armature 23 formed of soft iron or any other proper metal. The armature 23 conveniently has at its outer end a flange or head'portion 24. A spring 25 is interposed between the cap I and its head portion and normally urges the part to assume a position as shown in Fig. 1. Cap I2 may mount a casing 25 enclosing a switch structure which may be operated by an actuator 21 extending beyond the cap. A stop element 28 may be afiixed to the casing 26 in line with the path of travel of the plunger 23 so as to arrest outward movement of the parts. Leads 29 extend through the casing and are connected to the switch structure and to the windings of the solenoid Similarly the structure shown in Fig. 2 may mount a medicament-containing cartridge or ampule 5 upon its outer end portion 38 by means of a holder in the form of a ring 3|. The outer portion 30 may have screw-threaded attachment with a cap 32 which, in conjunction with a cylindrical body portion 33 and a rear portion 34, provides the main part of the assembly. Within the space thus defined, the windings of a solenoid 35 may be disposed. A plunger 36 may be projectable through the bore of part 30 and be attached to an armature 31.

Again in this form of the device the parts 35 to 34 inclusive and 3B are preferably formed of non-magnetic material such as brass. A stop 38 of soft iron may cooperate with plunger 3? which is likewise conveniently formed of this metal. The core 39 similar to the core |8 may be in the form of a tube having an internal diameter slightly in excess of the external diameter of the armature moveable within the same. This core may be formed of brass. Washers 4|] may be interposed between the ends of the Winding 35 and cap 32 and body portion 34. In order to avoid undue and unnecessary illustration, the spring, switch, and incidental portions of the apparatus have not been shown in Fig. 2.

In employing apparatus of this nature, the chamber which receives the medicament will have been charged with proper liquid and thereafter the leads 29 will have been connected to a sources of suitable current supply. As shown such charging will simply embrace the association of a cartridge or ampule 5 with the outer end of the device by bringing the parts into abutting position and thereafter applying and tightening It is of course obvious ampules might be employed. In certain instances the medicament might be retained in the body of the device. According to the needs of a given installation the outer end of plunger 2| or 36 could be modified in design. In any event with the discharge orifice or orifices of the assembly firmly pressed against the site of inj ection, the switch is closed; The resultant flow of current will energize the encasing structures l3, l4 and I5 of the solenoid, as well as a stop 22 which will instantaneously attract armature 23.

This attraction will continue until that plunger strikes against the stop 22.

The magnetic flux set-up will have no effect on plunger 2| or 36. With the movement of the armature 23 or 31 these non-magnetic plungers will bemoved outwardly at considerable speed. As will be understood, this speed will be substantial. With such outward movement, the end of the plunger 2| or 36 will strike against the stopper of the ampule or other medicament-receiving structure and will cause a piston-like action to occur such that the liquid will be expelled at high velocity and pressure through the minute discharge orifice 6. Thus the skin and tissues disposed adjacent the end wall of cartridge 5 will be penetrated by the medicament. When the switch 21 is released, current flow will be interrupted and under the influence of spring 25, the parts will return to their initial positions.

With the parts proportioned and arranged as shown, an initial pull will be exerted as the circuit is closed. Due to the characteristics of the ironclad solenoid and stop, an increasing pull is assured as the plunger moves through its discharge stroke. A maximum pull results as the plunger shifts to a position adjacent its stop. Thus, the rate of discharge of the medicament does not decrease throughthe working stroke, with resultant inefiiciency of the injection.

Thus, among others, the several objects of the invention as afore noted are achieved. Obviously numerous changes in construction and re arrangement of the parts might be resorted to without departing from the spirit of the invention as defined by the claims.

I claim:

1. A device for injecting medicament at velocities and in a sufficiently fine stream such that it will penetrate and lodge within underlying tissues without the aid of a skin-penetrating needle, said device including in combination a body formed with a bore, means providing a medicament receiving chamber at one end of said body in line with said bore, a solenoid encircling said bore at a point short of said chamber, an armature movably supported within the bore of said body to be shifted responsive to solenoid energization and means connected to said armature and cooperable with said chamber for expelling medicament therefrom as said armature is so shifted.

2. A device for injecting medicament at velocities and in a sufiiciently fine stream such that it will penetrate and lodge Within underlying tissues without the aid of a skin-penetrating needle, said device including in combination a body formed with a bore, means providing a medicament receiving chamber at one end of said body in line with said bore, a solenoid encircling said bore at a point short of said chamber, an armature movably supported within the bore of said body to be shifted responsive to solenoid energization, means connected to said armature and cooperable with said chamber for expelling medicament therefrom as said armature is so shifted and a spring also disposed in said bore urging said armature direction.

3. A device for injecting medicament at velocities and in a sufficiently fine stream such that it will penetrate and lodge within underlying tissues without the aid of a skin-penetrating needle, said device including in combination a body formed with a bore, means providing a medicament receiving chamber at one end of in an, opposite said body in line with said bore, a solenoid encircling said bore at a point short of said chamber, an armature movably supported within the bore of said body to be shifted responsive to solenoid energization, means connected to said armature and cooperable with said chamber for expelling medicament therefrom as said armature is so shifted and a switch adjacent the opposite end of said body and connected to said solenoid to control the flow of current therethrough.

4. A device for injecting medicament at velocities and in a sufiiciently fine stream such that it will penetrate and lodge within underlying tissues without the aid of a skin-penetrating needle, said device including in combination a body, means forming a part of said body and providing a detachable mounting for a unit embracing a medicament receiving chamber to be disposed adjacent one end of said body and beyond the same, a solenoid supported by said body at a point short of such end of the same, an armature movably mounted within said body to be shifted responsive to solenoid energization, means connected to said armature and under the shifting of the latter moving to a point beyond the end of the body to cooperate with the medicament receiving chamber mounted by the end of the latter and to expel medicament therefrom and means for normally retaining said expelling means at a point within said body.

5. A device for injecting medicament at velocities and in a sufliciently fine stream such that it will penetrate the skin and lodge within underlying tissues without the aid of a skin-penetrating needle, said device including in combination a body formed with a bore, means providing a medicament receiving chamber at one end of said body in line with said bore, a solenoid encircling said bore at a point short of said chamber, an armature movably supported within the bore of said body and normally extending beyond said solenoid in a direction opposite from that of said chamber, and non-magnetic means extending between said armature and chamber and cooperable with the latter for expelling medicament from the same as said armature shifts towards said solenoid.

6. A hypodermic injection device including in combination a body formed with a bore, means for mounting an ampule against movement with respect to said body and which ampule embraces a medicament chamber formed with a discharge orifice at one end and a piston at the opposite end thereof and movable through said chamber to expel medicament through such orifice, said mounting means supporting said ampule with its piston in line with said bore, an armature projectible within said bore to act against the ampule piston and a solenoid disposed at a point short of said ampule mounting means and enclosed within said body, said armature causing said piston to be projected and maintaining it so projected under continued energization of said solenoid.

7. A hypodermic injection device including in combination a body formed with a bore, means for mounting an ampule against movement with respect to said body and which ampule embraces a medicament chamber formed with a discharge orifice at one end and a piston at the opposite end thereof and movable through said chamber to expel medicament through such orifice, said mounting means supporting said ampule with its piston in line with said bore, an armature projectible within said bore to act against the ampule piston, a solenoid disposed at a point short of said ampule mounting means and enclosed within said body, said armature causing said piston to be projected and maintaining it so projected under continued energization of said solenoid and a spring within said body and acting against said armature to retract the latter upon interruption of solenoid energization.

8. A hypodermic injection device including in combination a body formed with a bore, means for mounting an ampule against movement with respect to said body and which ampule embraces a medicament chamber formed with a discharge orifice at one end and a piston at the opposite end thereof and movable through said chamber to expel medicament through such orifice, said mounting means supporting said ampule with its piston in line with said bore, an armature projectible within said bore to act against the am-- pule piston, a solenoid disposed at a point short of said ampule mounting means and enclosed within said body, said armature causing said piston to be projected and maintaining it'so projected under continued energization of said solenoid and a switch connected to said solenoid and supported by said body adjacent the end thereof opposite from that at which said ampule mounting means is disposed.

- GARWOOD W. FERGUSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,639,409 Johnson et a1 Aug. 16, 1927 1,881,963 Perrin Oct. 11, 1936 2,263,865 Bailen Nov. 25, 1941 2,322,244 Lockhart June 22, 1943 2,380,534 Lockhart July 31, 1945 2,410,692 Strobell Nov. 5, 1946 

